Boise Air Terminal Weather Records (USW00024131)
Record envelope, standing records and threshold days for Boise Air Terminal (USW00024131), Idaho, United States, with 87 years of record.
Key Facts for Boise Air Terminal
- Boise Air Terminal (USW00024131) is a weather station in Idaho, United States at 43.57 latitude and -116.24 longitude, 861 m (2,823 ft) above sea level.
- The station reports from 1940 to 2026, 87 years of record.
- 1,464 records set at Boise Air Terminal still stand.
- Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
- Boise Air Terminal set a daily record high minimum temperature of 12.8 C (55.0 F) on 6 October 2026 (provisional).
Provisional Records
Records set in the last 60 days are provisional until they clear the revision window.
About the Station
- Location: Idaho, United States, 43.57 latitude, -116.24 longitude.
- Elevation: 861 m (2,823 ft).
- Period of record: 1940 to 2026, 87 years.
- Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
9 days at or beyond a record| Month | Highest record high | Lowest record low | 2026 highest maximum | 2026 lowest minimum |
|---|---|---|---|---|
| Jan | 18.9 C (66.0 F) | -27.2 C (-17.0 F) | 15.0 C (59.0 F) | -9.4 C (15.1 F) |
| Feb | 21.7 C (71.1 F) | -26.1 C (-15.0 F) | 16.7 C (62.1 F) | -4.4 C (24.1 F) |
| Mar | 28.3 C (82.9 F) | -14.4 C (6.1 F) | 28.3 C (82.9 F) | -3.9 C (25.0 F) |
| Apr | 33.3 C (91.9 F) | -7.2 C (19.0 F) | 27.8 C (82.0 F) | -1.7 C (28.9 F) |
| May | 37.8 C (100.0 F) | -5.6 C (21.9 F) | 35.6 C (96.1 F) | 3.3 C (37.9 F) |
| Jun | 43.3 C (109.9 F) | -0.6 C (30.9 F) | 35.0 C (95.0 F) | 6.7 C (44.1 F) |
| Jul | 43.9 C (111.0 F) | 1.7 C (35.1 F) | 40.0 C (104.0 F) | 11.1 C (52.0 F) |
| Aug | 43.3 C (109.9 F) | 1.1 C (34.0 F) | 38.3 C (100.9 F) | 10.0 C (50.0 F) |
| Sep | 40.0 C (104.0 F) | -5.0 C (23.0 F) | 34.4 C (93.9 F) | 6.1 C (43.0 F) |
| Oct | 34.4 C (93.9 F) | -11.7 C (10.9 F) | 31.1 C (88.0 F) | 2.8 C (37.0 F) |
| Nov | 25.6 C (78.1 F) | -19.4 C (-2.9 F) | n/a | n/a |
| Dec | 18.3 C (64.9 F) | -31.7 C (-25.1 F) | n/a | n/a |
Which Years Hold Standing Records
1,464 standing records| Year set | Standing records |
|---|---|
| 1940 | 13 |
| 1941 | 13 |
| 1942 | 13 |
| 1943 | 13 |
| 1944 | 15 |
| 1945 | 19 |
| 1946 | 8 |
| 1947 | 13 |
| 1948 | 19 |
| 1949 | 21 |
| 1950 | 23 |
| 1951 | 9 |
| 1952 | 5 |
| 1953 | 15 |
| 1954 | 24 |
| 1955 | 28 |
| 1956 | 21 |
| 1957 | 10 |
| 1958 | 11 |
| 1959 | 12 |
| 1960 | 23 |
| 1961 | 14 |
| 1962 | 22 |
| 1963 | 28 |
| 1964 | 18 |
| 1965 | 25 |
| 1966 | 20 |
| 1967 | 9 |
| 1968 | 18 |
| 1969 | 17 |
| 1970 | 26 |
| 1971 | 17 |
| 1972 | 32 |
| 1973 | 10 |
| 1974 | 19 |
| 1975 | 21 |
| 1976 | 9 |
| 1977 | 20 |
| 1978 | 19 |
| 1979 | 11 |
| 1980 | 10 |
| 1981 | 12 |
| 1982 | 15 |
| 1983 | 15 |
| 1984 | 31 |
| 1985 | 47 |
| 1986 | 17 |
| 1987 | 27 |
| 1988 | 23 |
| 1989 | 20 |
| 1990 | 33 |
| 1991 | 13 |
| 1992 | 23 |
| 1993 | 28 |
| 1994 | 15 |
| 1995 | 24 |
| 1996 | 16 |
| 1997 | 10 |
| 1998 | 12 |
| 1999 | 11 |
| 2000 | 8 |
| 2001 | 11 |
| 2002 | 18 |
| 2003 | 26 |
| 2004 | 6 |
| 2005 | 10 |
| 2006 | 14 |
| 2007 | 15 |
| 2008 | 8 |
| 2009 | 16 |
| 2010 | 6 |
| 2011 | 11 |
| 2012 | 14 |
| 2013 | 12 |
| 2014 | 20 |
| 2015 | 31 |
| 2016 | 14 |
| 2017 | 18 |
| 2018 | 13 |
| 2019 | 6 |
| 2020 | 11 |
| 2021 | 10 |
| 2022 | 18 |
| 2023 | 13 |
| 2024 | 22 |
| 2025 | 17 |
| 2026 | 11 |
All-Time Record Progression
16 new records| Date | Kind | Detail |
|---|---|---|
| 1971-08-03 | Record high minimum temperature | Record high minimum temperature 25.0 C (77.0 F) |
| 1972-12-08 | Record low minimum temperature | Record low minimum temperature -28.3 C (-18.9 F) |
| 1972-12-09 | Record low minimum temperature | Record low minimum temperature -29.4 C (-20.9 F) |
| 1972-12-10 | Record low maximum temperature | Record low maximum temperature -18.3 C (-0.9 F) |
| 1972-12-10 | Record low minimum temperature | Record low minimum temperature -30.6 C (-23.1 F) |
| 1975-07-04 | Record high minimum temperature | Record high minimum temperature 25.6 C (78.1 F) |
| 1982-01-04 | Record snow depth | Record snow depth 30.5 cm (12.0 in) |
| 1983-12-30 | Record snow depth | Record snow depth 33.0 cm (13.0 in) |
| 1990-12-21 | Record low maximum temperature | Record low maximum temperature -19.4 C (-2.9 F) |
| 1990-12-22 | Record low maximum temperature | Record low maximum temperature -21.1 C (-6.0 F) |
| 1990-12-22 | Record low minimum temperature | Record low minimum temperature -31.7 C (-25.1 F) |
| 1994-07-30 | Record high minimum temperature | Record high minimum temperature 26.1 C (79.0 F) |
| 1996-12-20 | Record daily snowfall | Record daily snowfall 24.9 cm (9.8 in) |
| 2017-01-05 | Record snow depth | Record snow depth 38.0 cm (15.0 in) |
| 2021-07-19 | Record high minimum temperature | Record high minimum temperature 26.7 C (80.1 F) |
| 2024-07-22 | Record high minimum temperature | Record high minimum temperature 27.8 C (82.0 F) |
Wettest Day of Each Month
Jun: 48.5 mm (1.9 in)| Month | Record daily precipitation (mm) | Date |
|---|---|---|
| Jan | 28.7 mm (1.1 in) | 18 January 1953 |
| Feb | 23.4 mm (0.9 in) | 4 February 1951 |
| Mar | 40.6 mm (1.6 in) | 20 March 1981 |
| Apr | 32.3 mm (1.3 in) | 6 April 1969 |
| May | 45.0 mm (1.8 in) | 29 May 1990 |
| Jun | 48.5 mm (1.9 in) | 12 June 1958 |
| Jul | 23.9 mm (0.9 in) | 30 July 1960 |
| Aug | 40.9 mm (1.6 in) | 13 August 1979 |
| Sep | 43.9 mm (1.7 in) | 11 September 1976 |
| Oct | 24.1 mm (0.9 in) | 9 October 2018 |
| Nov | 29.2 mm (1.1 in) | 1 November 2014 |
| Dec | 26.2 mm (1.0 in) | 23 December 1955 |
Period of Record Coverage
1940 to 2026| Year | Days with data | Share of year | Complete |
|---|---|---|---|
| 1940 | 366 | 100% | Yes |
| 1941 | 365 | 100% | Yes |
| 1942 | 365 | 100% | Yes |
| 1943 | 365 | 100% | Yes |
| 1944 | 366 | 100% | Yes |
| 1945 | 365 | 100% | Yes |
| 1946 | 365 | 100% | Yes |
| 1947 | 365 | 100% | Yes |
| 1948 | 366 | 100% | Yes |
| 1949 | 365 | 100% | Yes |
| 1950 | 365 | 100% | Yes |
| 1951 | 365 | 100% | Yes |
| 1952 | 366 | 100% | Yes |
| 1953 | 365 | 100% | Yes |
| 1954 | 365 | 100% | Yes |
| 1955 | 365 | 100% | Yes |
| 1956 | 366 | 100% | Yes |
| 1957 | 365 | 100% | Yes |
| 1958 | 365 | 100% | Yes |
| 1959 | 365 | 100% | Yes |
| 1960 | 366 | 100% | Yes |
| 1961 | 365 | 100% | Yes |
| 1962 | 365 | 100% | Yes |
| 1963 | 365 | 100% | Yes |
| 1964 | 366 | 100% | Yes |
| 1965 | 365 | 100% | Yes |
| 1966 | 365 | 100% | Yes |
| 1967 | 365 | 100% | Yes |
| 1968 | 366 | 100% | Yes |
| 1969 | 365 | 100% | Yes |
| 1970 | 365 | 100% | Yes |
| 1971 | 365 | 100% | Yes |
| 1972 | 366 | 100% | Yes |
| 1973 | 365 | 100% | Yes |
| 1974 | 365 | 100% | Yes |
| 1975 | 365 | 100% | Yes |
| 1976 | 366 | 100% | Yes |
| 1977 | 365 | 100% | Yes |
| 1978 | 365 | 100% | Yes |
| 1979 | 365 | 100% | Yes |
| 1980 | 366 | 100% | Yes |
| 1981 | 365 | 100% | Yes |
| 1982 | 365 | 100% | Yes |
| 1983 | 365 | 100% | Yes |
| 1984 | 366 | 100% | Yes |
| 1985 | 365 | 100% | Yes |
| 1986 | 365 | 100% | Yes |
| 1987 | 365 | 100% | Yes |
| 1988 | 366 | 100% | Yes |
| 1989 | 365 | 100% | Yes |
| 1990 | 365 | 100% | Yes |
| 1991 | 365 | 100% | Yes |
| 1992 | 366 | 100% | Yes |
| 1993 | 365 | 100% | Yes |
| 1994 | 365 | 100% | Yes |
| 1995 | 365 | 100% | Yes |
| 1996 | 366 | 100% | Yes |
| 1997 | 365 | 100% | Yes |
| 1998 | 365 | 100% | Yes |
| 1999 | 365 | 100% | Yes |
| 2000 | 366 | 100% | Yes |
| 2001 | 365 | 100% | Yes |
| 2002 | 365 | 100% | Yes |
| 2003 | 365 | 100% | Yes |
| 2004 | 366 | 100% | Yes |
| 2005 | 365 | 100% | Yes |
| 2006 | 365 | 100% | Yes |
| 2007 | 365 | 100% | Yes |
| 2008 | 366 | 100% | Yes |
| 2009 | 365 | 100% | Yes |
| 2010 | 365 | 100% | Yes |
| 2011 | 365 | 100% | Yes |
| 2012 | 366 | 100% | Yes |
| 2013 | 365 | 100% | Yes |
| 2014 | 365 | 100% | Yes |
| 2015 | 365 | 100% | Yes |
| 2016 | 366 | 100% | Yes |
| 2017 | 365 | 100% | Yes |
| 2018 | 365 | 100% | Yes |
| 2019 | 365 | 100% | Yes |
| 2020 | 366 | 100% | Yes |
| 2021 | 365 | 100% | Yes |
| 2022 | 365 | 100% | Yes |
| 2023 | 365 | 100% | Yes |
| 2024 | 366 | 100% | Yes |
| 2025 | 365 | 100% | Yes |
| 2026 | 286 | 78% | No |
Latest Records
20| Date | Station | Record | Value | Beat old record by | Old record stood | Significance |
|---|---|---|---|---|---|---|
| 6 October 2026 | Boise Air Terminal, US | daily high min (Provisional) | 12.8 C (55.0 F) | 0.6 C (1.1 F) | 23 years | 15 of 100 (Routine) |
| 4 October 2026 | Boise Air Terminal, US | daily high max (Tie, Provisional) | 31.1 C (88.0 F) | tie | 79 years | 7 of 100 (Routine) |
| 4 September 2026 | Boise Air Terminal, US | daily low max (Provisional) | 14.4 C (57.9 F) | 3.9 C (7.0 F) | 9 years | 17 of 100 (Routine) |
| 27 August 2026 | Boise Air Terminal, US | daily high min (Tie, Provisional) | 21.1 C (70.0 F) | tie | 11 years | 2 of 100 (Routine) |
| 26 August 2026 | Boise Air Terminal, US | daily high min (Provisional) | 22.2 C (72.0 F) | 1.6 C (2.9 F) | 16 years | 16 of 100 (Routine) |
| 25 August 2026 | Boise Air Terminal, US | daily high min (Tie, Provisional) | 21.1 C (70.0 F) | tie | 3 years | 2 of 100 (Routine) |
| 22 August 2026 | Boise Air Terminal, US | daily high min (Provisional) | 24.4 C (75.9 F) | 2.7 C (4.9 F) | 20 years | 21 of 100 (Routine) |
| 21 August 2026 | Boise Air Terminal, US | daily high max (Tie, Provisional) | 38.3 C (100.9 F) | tie | 20 years | 3 of 100 (Routine) |
| 21 July 2026 | Boise Air Terminal, US | daily high min (Tie) | 22.8 C (73.0 F) | tie | 48 years | 5 of 100 (Routine) |
| 20 July 2026 | Boise Air Terminal, US | daily high max | 40.0 C (104.0 F) | 0.6 C (1.1 F) | 65 years | 28 of 100 (Routine) |
| 17 July 2026 | Boise Air Terminal, US | daily rain | 4.1 mm (0.16 in) | 2.8 mm (0.11 in) | 21 years | 20 of 100 (Routine) |
| 12 May 2026 | Boise Air Terminal, US | daily high max | 35.6 C (96.1 F) | 1.2 C (2.2 F) | 32 years | 19 of 100 (Routine) |
| 22 April 2026 | Boise Air Terminal, US | daily rain | 22.1 mm (0.9 in) | 13.0 mm (0.5 in) | 12 years | 20 of 100 (Routine) |
| 15 April 2026 | Boise Air Terminal, US | daily rain | 13.5 mm (0.5 in) | 3.8 mm (0.15 in) | 49 years | 20 of 100 (Routine) |
| 12 April 2026 | Boise Air Terminal, US | daily rain | 19.8 mm (0.8 in) | 12.9 mm (0.5 in) | 60 years | 20 of 100 (Routine) |
| 10 April 2026 | Boise Air Terminal, US | daily rain | 9.9 mm (0.39 in) | 3.3 mm (0.13 in) | 60 years | 20 of 100 (Routine) |
| 10 April 2026 | Boise Air Terminal, US | daily high min | 10.6 C (51.1 F) | 0.6 C (1.1 F) | 40 years | 21 of 100 (Routine) |
| 25 March 2026 | Boise Air Terminal, US | daily high min | 10.0 C (50.0 F) | 1.1 C (2.0 F) | 85 years | 35 of 100 (Notable) |
| 24 March 2026 | Boise Air Terminal, US | daily high max | 23.9 C (75.0 F) | 0.6 C (1.1 F) | 69 years | 29 of 100 (Routine) |
| 24 March 2026 | Boise Air Terminal, US | daily high min | 10.0 C (50.0 F) | 1.1 C (2.0 F) | 28 years | 18 of 100 (Routine) |
Climate Trend
86 complete years, 1940 to 2025| Year | Annual mean temperature | Difference from the station mean |
|---|---|---|
| 1940 | 11.7 C | +0.66 C |
| 1941 | 11.0 C | +0.01 C |
| 1942 | 9.8 C | -1.21 C |
| 1943 | 10.5 C | -0.48 C |
| 1944 | 9.9 C | -1.09 C |
| 1945 | 10.4 C | -0.65 C |
| 1946 | 10.5 C | -0.55 C |
| 1947 | 10.6 C | -0.43 C |
| 1948 | 9.6 C | -1.41 C |
| 1949 | 10.0 C | -0.98 C |
| 1950 | 10.5 C | -0.52 C |
| 1951 | 10.0 C | -1.02 C |
| 1952 | 10.3 C | -0.74 C |
| 1953 | 10.8 C | -0.16 C |
| 1954 | 10.7 C | -0.28 C |
| 1955 | 9.2 C | -1.77 C |
| 1956 | 10.1 C | -0.90 C |
| 1957 | 10.0 C | -0.98 C |
| 1958 | 11.7 C | +0.68 C |
| 1959 | 10.2 C | -0.82 C |
| 1960 | 10.6 C | -0.45 C |
| 1961 | 11.2 C | +0.17 C |
| 1962 | 10.2 C | -0.84 C |
| 1963 | 11.4 C | +0.38 C |
| 1964 | 9.1 C | -1.87 C |
| 1965 | 10.6 C | -0.44 C |
| 1966 | 10.9 C | -0.10 C |
| 1967 | 11.3 C | +0.25 C |
| 1968 | 11.2 C | +0.24 C |
| 1969 | 11.0 C | -0.05 C |
| 1970 | 11.1 C | +0.06 C |
| 1971 | 10.8 C | -0.22 C |
| 1972 | 10.5 C | -0.52 C |
| 1973 | 11.6 C | +0.59 C |
| 1974 | 11.2 C | +0.17 C |
| 1975 | 10.4 C | -0.61 C |
| 1976 | 9.9 C | -1.08 C |
| 1977 | 10.4 C | -0.60 C |
| 1978 | 10.5 C | -0.46 C |
| 1979 | 10.2 C | -0.81 C |
| 1980 | 10.5 C | -0.51 C |
| 1981 | 10.9 C | -0.08 C |
| 1982 | 9.2 C | -1.77 C |
| 1983 | 10.6 C | -0.39 C |
| 1984 | 8.8 C | -2.21 C |
| 1985 | 7.7 C | -3.33 C |
| 1986 | 11.0 C | -0.01 C |
| 1987 | 11.5 C | +0.53 C |
| 1988 | 11.1 C | +0.07 C |
| 1989 | 10.0 C | -0.98 C |
| 1990 | 10.9 C | -0.07 C |
| 1991 | 10.6 C | -0.38 C |
| 1992 | 11.8 C | +0.80 C |
| 1993 | 9.3 C | -1.74 C |
| 1994 | 11.3 C | +0.29 C |
| 1995 | 11.2 C | +0.24 C |
| 1996 | 11.3 C | +0.25 C |
| 1997 | 11.6 C | +0.58 C |
| 1998 | 12.1 C | +1.05 C |
| 1999 | 11.5 C | +0.45 C |
| 2000 | 11.5 C | +0.51 C |
| 2001 | 11.5 C | +0.53 C |
| 2002 | 11.3 C | +0.31 C |
| 2003 | 12.7 C | +1.65 C |
| 2004 | 11.7 C | +0.70 C |
| 2005 | 11.3 C | +0.32 C |
| 2006 | 12.1 C | +1.05 C |
| 2007 | 12.3 C | +1.30 C |
| 2008 | 11.3 C | +0.31 C |
| 2009 | 11.4 C | +0.42 C |
| 2010 | 11.8 C | +0.82 C |
| 2011 | 11.3 C | +0.32 C |
| 2012 | 12.9 C | +1.93 C |
| 2013 | 11.0 C | -0.02 C |
| 2014 | 12.3 C | +1.31 C |
| 2015 | 13.0 C | +1.96 C |
| 2016 | 12.4 C | +1.42 C |
| 2017 | 11.6 C | +0.60 C |
| 2018 | 12.2 C | +1.24 C |
| 2019 | 11.6 C | +0.60 C |
| 2020 | 12.2 C | +1.22 C |
| 2021 | 12.9 C | +1.87 C |
| 2022 | 11.5 C | +0.45 C |
| 2023 | 12.5 C | +1.52 C |
| 2024 | 13.0 C | +1.99 C |
| 2025 | 13.0 C | +2.00 C |
The annual mean temperature here has risen by 0.3 C (0.2 to 0.3) per decade over 1940 to 2025. In Fahrenheit: 0.5 F (0.3 to 0.6) per decade. The slope is a straight line fitted to 86 complete years; the brackets give its 95 percent interval.
| Measure | Per decade (C) | Per decade (F) | Period | Complete years | Reading |
|---|---|---|---|---|---|
| Annual mean temperature | 0.3 C (0.2 to 0.3) per decade | 0.5 F (0.3 to 0.6) per decade | 1940 to 2025 | 86 | Rise |
| Mean daily maximum | 0.2 C (0.1 to 0.3) per decade | 0.4 F (0.3 to 0.5) per decade | 1940 to 2025 | 86 | Rise |
| Mean daily minimum | 0.3 C (0.2 to 0.4) per decade | 0.5 F (0.4 to 0.7) per decade | 1940 to 2025 | 86 | Rise |
A year is complete when all 12 months have at least 20 days of both daily maximum and daily minimum readings. The annual mean is the mean of the monthly means. The trend describes this one station over this period; it does not say what caused the change.
Extremes by Year
1940 to 2026| Measure | Record | Year of the record | Median year | Years with a value |
|---|---|---|---|---|
| Hottest day (TXx) | 43.9 C (111.0 F) | 1960 | 40.0 C (104.0 F) | 87 |
| Coldest night (TNn) | -31.7 C (-25.1 F) | 1990 | -17.2 C (1.0 F) | 87 |
| Wettest day (Rx1day) | 48.5 mm (1.9 in) | 1958 | 20.1 mm (0.8 in) | 87 |
| Wettest five days (Rx5day) | 71.9 mm (2.8 in) | 1990 | 34.5 mm (1.4 in) | 87 |
| Longest dry spell (CDD) | 107 days | 1942 | 50 days | 87 |
Hottest day (TXx)
| Year | Hottest day (TXx) |
|---|---|
| 1940 | 42.8 C (109.0 F) |
| 1941 | 38.3 C (100.9 F) |
| 1942 | 40.0 C (104.0 F) |
| 1943 | 38.9 C (102.0 F) |
| 1944 | 37.2 C (99.0 F) |
| 1945 | 38.9 C (102.0 F) |
| 1946 | 40.6 C (105.1 F) |
| 1947 | 40.0 C (104.0 F) |
| 1948 | 37.2 C (99.0 F) |
| 1949 | 40.6 C (105.1 F) |
| 1950 | 39.4 C (102.9 F) |
| 1951 | 39.4 C (102.9 F) |
| 1952 | 36.7 C (98.1 F) |
| 1953 | 40.6 C (105.1 F) |
| 1954 | 37.8 C (100.0 F) |
| 1955 | 40.6 C (105.1 F) |
| 1956 | 41.1 C (106.0 F) |
| 1957 | 37.8 C (100.0 F) |
| 1958 | 37.8 C (100.0 F) |
| 1959 | 41.1 C (106.0 F) |
| 1960 | 43.9 C (111.0 F) |
| 1961 | 43.3 C (109.9 F) |
| 1962 | 38.9 C (102.0 F) |
| 1963 | 40.0 C (104.0 F) |
| 1964 | 38.3 C (100.9 F) |
| 1965 | 39.4 C (102.9 F) |
| 1966 | 39.4 C (102.9 F) |
| 1967 | 41.7 C (107.1 F) |
| 1968 | 40.0 C (104.0 F) |
| 1969 | 41.7 C (107.1 F) |
| 1970 | 38.9 C (102.0 F) |
| 1971 | 40.0 C (104.0 F) |
| 1972 | 38.9 C (102.0 F) |
| 1973 | 39.4 C (102.9 F) |
| 1974 | 40.6 C (105.1 F) |
| 1975 | 42.2 C (108.0 F) |
| 1976 | 39.4 C (102.9 F) |
| 1977 | 38.9 C (102.0 F) |
| 1978 | 40.6 C (105.1 F) |
| 1979 | 38.9 C (102.0 F) |
| 1980 | 41.1 C (106.0 F) |
| 1981 | 38.9 C (102.0 F) |
| 1982 | 36.7 C (98.1 F) |
| 1983 | 41.1 C (106.0 F) |
| 1984 | 40.0 C (104.0 F) |
| 1985 | 38.3 C (100.9 F) |
| 1986 | 40.6 C (105.1 F) |
| 1987 | 40.0 C (104.0 F) |
| 1988 | 40.0 C (104.0 F) |
| 1989 | 42.2 C (108.0 F) |
| 1990 | 42.8 C (109.0 F) |
| 1991 | 39.4 C (102.9 F) |
| 1992 | 41.1 C (106.0 F) |
| 1993 | 38.9 C (102.0 F) |
| 1994 | 41.1 C (106.0 F) |
| 1995 | 38.9 C (102.0 F) |
| 1996 | 40.0 C (104.0 F) |
| 1997 | 38.3 C (100.9 F) |
| 1998 | 42.2 C (108.0 F) |
| 1999 | 38.9 C (102.0 F) |
| 2000 | 38.9 C (102.0 F) |
| 2001 | 41.1 C (106.0 F) |
| 2002 | 43.3 C (109.9 F) |
| 2003 | 42.2 C (108.0 F) |
| 2004 | 40.0 C (104.0 F) |
| 2005 | 41.7 C (107.1 F) |
| 2006 | 41.7 C (107.1 F) |
| 2007 | 40.6 C (105.1 F) |
| 2008 | 40.6 C (105.1 F) |
| 2009 | 41.1 C (106.0 F) |
| 2010 | 40.0 C (104.0 F) |
| 2011 | 39.4 C (102.9 F) |
| 2012 | 42.2 C (108.0 F) |
| 2013 | 43.3 C (109.9 F) |
| 2014 | 40.0 C (104.0 F) |
| 2015 | 43.3 C (109.9 F) |
| 2016 | 38.9 C (102.0 F) |
| 2017 | 40.0 C (104.0 F) |
| 2018 | 43.3 C (109.9 F) |
| 2019 | 38.9 C (102.0 F) |
| 2020 | 40.6 C (105.1 F) |
| 2021 | 41.7 C (107.1 F) |
| 2022 | 41.1 C (106.0 F) |
| 2023 | 40.6 C (105.1 F) |
| 2024 | 42.2 C (108.0 F) |
| 2025 | 40.0 C (104.0 F) |
| 2026 | 40.0 C (104.0 F) |
Coldest night (TNn)
| Year | Coldest night (TNn) |
|---|---|
| 1940 | -12.8 C (9.0 F) |
| 1941 | -17.8 C (0.0 F) |
| 1942 | -25.0 C (-13.0 F) |
| 1943 | -23.3 C (-9.9 F) |
| 1944 | -17.8 C (0.0 F) |
| 1945 | -17.8 C (0.0 F) |
| 1946 | -11.7 C (10.9 F) |
| 1947 | -23.3 C (-9.9 F) |
| 1948 | -17.8 C (0.0 F) |
| 1949 | -21.7 C (-7.1 F) |
| 1950 | -27.2 C (-17.0 F) |
| 1951 | -17.2 C (1.0 F) |
| 1952 | -18.9 C (-2.0 F) |
| 1953 | -10.6 C (12.9 F) |
| 1954 | -13.9 C (7.0 F) |
| 1955 | -19.4 C (-2.9 F) |
| 1956 | -21.1 C (-6.0 F) |
| 1957 | -22.8 C (-9.0 F) |
| 1958 | -10.6 C (12.9 F) |
| 1959 | -16.1 C (3.0 F) |
| 1960 | -20.0 C (-4.0 F) |
| 1961 | -15.6 C (3.9 F) |
| 1962 | -24.4 C (-11.9 F) |
| 1963 | -21.7 C (-7.1 F) |
| 1964 | -17.2 C (1.0 F) |
| 1965 | -13.3 C (8.1 F) |
| 1966 | -16.7 C (1.9 F) |
| 1967 | -16.7 C (1.9 F) |
| 1968 | -14.4 C (6.1 F) |
| 1969 | -15.0 C (5.0 F) |
| 1970 | -15.0 C (5.0 F) |
| 1971 | -14.4 C (6.1 F) |
| 1972 | -30.6 C (-23.1 F) |
| 1973 | -11.7 C (10.9 F) |
| 1974 | -20.6 C (-5.1 F) |
| 1975 | -20.6 C (-5.1 F) |
| 1976 | -16.1 C (3.0 F) |
| 1977 | -25.6 C (-14.1 F) |
| 1978 | -22.8 C (-9.0 F) |
| 1979 | -25.0 C (-13.0 F) |
| 1980 | -21.7 C (-7.1 F) |
| 1981 | -15.0 C (5.0 F) |
| 1982 | -23.3 C (-9.9 F) |
| 1983 | -27.8 C (-18.0 F) |
| 1984 | -25.0 C (-13.0 F) |
| 1985 | -24.4 C (-11.9 F) |
| 1986 | -17.2 C (1.0 F) |
| 1987 | -17.8 C (0.0 F) |
| 1988 | -20.0 C (-4.0 F) |
| 1989 | -26.1 C (-15.0 F) |
| 1990 | -31.7 C (-25.1 F) |
| 1991 | -24.4 C (-11.9 F) |
| 1992 | -17.8 C (0.0 F) |
| 1993 | -17.8 C (0.0 F) |
| 1994 | -13.9 C (7.0 F) |
| 1995 | -12.8 C (9.0 F) |
| 1996 | -17.2 C (1.0 F) |
| 1997 | -13.3 C (8.1 F) |
| 1998 | -18.9 C (-2.0 F) |
| 1999 | -8.9 C (16.0 F) |
| 2000 | -10.0 C (14.0 F) |
| 2001 | -13.9 C (7.0 F) |
| 2002 | -11.1 C (12.0 F) |
| 2003 | -8.9 C (16.0 F) |
| 2004 | -17.2 C (1.0 F) |
| 2005 | -13.9 C (7.0 F) |
| 2006 | -12.2 C (10.0 F) |
| 2007 | -13.9 C (7.0 F) |
| 2008 | -15.0 C (5.0 F) |
| 2009 | -21.1 C (-6.0 F) |
| 2010 | -13.9 C (7.0 F) |
| 2011 | -12.8 C (9.0 F) |
| 2012 | -10.6 C (12.9 F) |
| 2013 | -21.6 C (-6.9 F) |
| 2014 | -17.1 C (1.2 F) |
| 2015 | -14.3 C (6.3 F) |
| 2016 | -17.7 C (0.1 F) |
| 2017 | -23.8 C (-10.8 F) |
| 2018 | -12.7 C (9.1 F) |
| 2019 | -12.1 C (10.2 F) |
| 2020 | -8.8 C (16.2 F) |
| 2021 | -12.7 C (9.1 F) |
| 2022 | -19.3 C (-2.7 F) |
| 2023 | -12.7 C (9.1 F) |
| 2024 | -16.0 C (3.2 F) |
| 2025 | -14.9 C (5.2 F) |
| 2026 | -9.4 C (15.1 F) |
Wettest day (Rx1day)
| Year | Wettest day (Rx1day) |
|---|---|
| 1940 | 19.1 mm (0.8 in) |
| 1941 | 24.6 mm (1.0 in) |
| 1942 | 28.7 mm (1.1 in) |
| 1943 | 26.7 mm (1.1 in) |
| 1944 | 19.8 mm (0.8 in) |
| 1945 | 17.8 mm (0.7 in) |
| 1946 | 11.7 mm (0.5 in) |
| 1947 | 13.7 mm (0.5 in) |
| 1948 | 18.3 mm (0.7 in) |
| 1949 | 14.2 mm (0.6 in) |
| 1950 | 25.4 mm (1.0 in) |
| 1951 | 23.4 mm (0.9 in) |
| 1952 | 22.4 mm (0.9 in) |
| 1953 | 28.7 mm (1.1 in) |
| 1954 | 17.0 mm (0.7 in) |
| 1955 | 26.2 mm (1.0 in) |
| 1956 | 26.9 mm (1.1 in) |
| 1957 | 19.1 mm (0.8 in) |
| 1958 | 48.5 mm (1.9 in) |
| 1959 | 16.8 mm (0.7 in) |
| 1960 | 23.9 mm (0.9 in) |
| 1961 | 17.5 mm (0.7 in) |
| 1962 | 27.7 mm (1.1 in) |
| 1963 | 16.8 mm (0.7 in) |
| 1964 | 26.2 mm (1.0 in) |
| 1965 | 19.6 mm (0.8 in) |
| 1966 | 10.2 mm (0.4 in) |
| 1967 | 15.7 mm (0.6 in) |
| 1968 | 17.0 mm (0.7 in) |
| 1969 | 32.3 mm (1.3 in) |
| 1970 | 18.0 mm (0.7 in) |
| 1971 | 19.8 mm (0.8 in) |
| 1972 | 14.5 mm (0.6 in) |
| 1973 | 21.3 mm (0.8 in) |
| 1974 | 16.5 mm (0.6 in) |
| 1975 | 12.4 mm (0.5 in) |
| 1976 | 43.9 mm (1.7 in) |
| 1977 | 28.2 mm (1.1 in) |
| 1978 | 15.5 mm (0.6 in) |
| 1979 | 40.9 mm (1.6 in) |
| 1980 | 24.1 mm (0.9 in) |
| 1981 | 40.6 mm (1.6 in) |
| 1982 | 17.3 mm (0.7 in) |
| 1983 | 27.9 mm (1.1 in) |
| 1984 | 22.9 mm (0.9 in) |
| 1985 | 19.8 mm (0.8 in) |
| 1986 | 19.3 mm (0.8 in) |
| 1987 | 17.8 mm (0.7 in) |
| 1988 | 20.1 mm (0.8 in) |
| 1989 | 16.5 mm (0.6 in) |
| 1990 | 45.0 mm (1.8 in) |
| 1991 | 16.3 mm (0.6 in) |
| 1992 | 14.7 mm (0.6 in) |
| 1993 | 22.4 mm (0.9 in) |
| 1994 | 16.5 mm (0.6 in) |
| 1995 | 15.2 mm (0.6 in) |
| 1996 | 18.0 mm (0.7 in) |
| 1997 | 20.8 mm (0.8 in) |
| 1998 | 24.6 mm (1.0 in) |
| 1999 | 10.9 mm (0.4 in) |
| 2000 | 22.9 mm (0.9 in) |
| 2001 | 18.8 mm (0.7 in) |
| 2002 | 21.8 mm (0.9 in) |
| 2003 | 18.3 mm (0.7 in) |
| 2004 | 16.8 mm (0.7 in) |
| 2005 | 22.4 mm (0.9 in) |
| 2006 | 16.8 mm (0.7 in) |
| 2007 | 20.1 mm (0.8 in) |
| 2008 | 22.9 mm (0.9 in) |
| 2009 | 23.1 mm (0.9 in) |
| 2010 | 35.8 mm (1.4 in) |
| 2011 | 19.6 mm (0.8 in) |
| 2012 | 27.7 mm (1.1 in) |
| 2013 | 18.3 mm (0.7 in) |
| 2014 | 29.2 mm (1.1 in) |
| 2015 | 17.0 mm (0.7 in) |
| 2016 | 11.9 mm (0.5 in) |
| 2017 | 35.6 mm (1.4 in) |
| 2018 | 24.1 mm (0.9 in) |
| 2019 | 21.1 mm (0.8 in) |
| 2020 | 30.7 mm (1.2 in) |
| 2021 | 21.1 mm (0.8 in) |
| 2022 | 20.1 mm (0.8 in) |
| 2023 | 37.1 mm (1.5 in) |
| 2024 | 27.7 mm (1.1 in) |
| 2025 | 23.6 mm (0.9 in) |
| 2026 | 22.1 mm (0.9 in) |
Wettest five days (Rx5day)
| Year | Wettest five days (Rx5day) |
|---|---|
| 1940 | 30.3 mm (1.2 in) |
| 1941 | 51.0 mm (2.0 in) |
| 1942 | 42.7 mm (1.7 in) |
| 1943 | 36.4 mm (1.4 in) |
| 1944 | 34.9 mm (1.4 in) |
| 1945 | 30.9 mm (1.2 in) |
| 1946 | 20.1 mm (0.8 in) |
| 1947 | 26.4 mm (1.0 in) |
| 1948 | 30.0 mm (1.2 in) |
| 1949 | 26.2 mm (1.0 in) |
| 1950 | 37.1 mm (1.5 in) |
| 1951 | 41.7 mm (1.6 in) |
| 1952 | 32.6 mm (1.3 in) |
| 1953 | 61.0 mm (2.4 in) |
| 1954 | 19.5 mm (0.8 in) |
| 1955 | 33.1 mm (1.3 in) |
| 1956 | 27.2 mm (1.1 in) |
| 1957 | 32.0 mm (1.3 in) |
| 1958 | 58.7 mm (2.3 in) |
| 1959 | 30.5 mm (1.2 in) |
| 1960 | 44.0 mm (1.7 in) |
| 1961 | 24.4 mm (1.0 in) |
| 1962 | 48.7 mm (1.9 in) |
| 1963 | 43.7 mm (1.7 in) |
| 1964 | 35.7 mm (1.4 in) |
| 1965 | 34.1 mm (1.3 in) |
| 1966 | 19.9 mm (0.8 in) |
| 1967 | 16.8 mm (0.7 in) |
| 1968 | 34.6 mm (1.4 in) |
| 1969 | 45.2 mm (1.8 in) |
| 1970 | 41.0 mm (1.6 in) |
| 1971 | 35.3 mm (1.4 in) |
| 1972 | 40.8 mm (1.6 in) |
| 1973 | 37.8 mm (1.5 in) |
| 1974 | 21.1 mm (0.8 in) |
| 1975 | 32.0 mm (1.3 in) |
| 1976 | 51.1 mm (2.0 in) |
| 1977 | 32.2 mm (1.3 in) |
| 1978 | 25.7 mm (1.0 in) |
| 1979 | 42.2 mm (1.7 in) |
| 1980 | 54.1 mm (2.1 in) |
| 1981 | 52.6 mm (2.1 in) |
| 1982 | 30.7 mm (1.2 in) |
| 1983 | 61.0 mm (2.4 in) |
| 1984 | 28.0 mm (1.1 in) |
| 1985 | 32.8 mm (1.3 in) |
| 1986 | 46.2 mm (1.8 in) |
| 1987 | 21.6 mm (0.9 in) |
| 1988 | 30.3 mm (1.2 in) |
| 1989 | 24.2 mm (1.0 in) |
| 1990 | 71.9 mm (2.8 in) |
| 1991 | 22.2 mm (0.9 in) |
| 1992 | 26.9 mm (1.1 in) |
| 1993 | 41.4 mm (1.6 in) |
| 1994 | 29.9 mm (1.2 in) |
| 1995 | 34.4 mm (1.4 in) |
| 1996 | 43.0 mm (1.7 in) |
| 1997 | 34.5 mm (1.4 in) |
| 1998 | 39.3 mm (1.5 in) |
| 1999 | 24.4 mm (1.0 in) |
| 2000 | 40.4 mm (1.6 in) |
| 2001 | 25.7 mm (1.0 in) |
| 2002 | 33.7 mm (1.3 in) |
| 2003 | 32.4 mm (1.3 in) |
| 2004 | 27.3 mm (1.1 in) |
| 2005 | 47.6 mm (1.9 in) |
| 2006 | 43.0 mm (1.7 in) |
| 2007 | 20.6 mm (0.8 in) |
| 2008 | 23.9 mm (0.9 in) |
| 2009 | 44.2 mm (1.7 in) |
| 2010 | 46.1 mm (1.8 in) |
| 2011 | 27.7 mm (1.1 in) |
| 2012 | 54.6 mm (2.1 in) |
| 2013 | 31.6 mm (1.2 in) |
| 2014 | 49.8 mm (2.0 in) |
| 2015 | 24.9 mm (1.0 in) |
| 2016 | 20.1 mm (0.8 in) |
| 2017 | 47.8 mm (1.9 in) |
| 2018 | 29.8 mm (1.2 in) |
| 2019 | 49.2 mm (1.9 in) |
| 2020 | 45.9 mm (1.8 in) |
| 2021 | 35.5 mm (1.4 in) |
| 2022 | 29.1 mm (1.1 in) |
| 2023 | 59.7 mm (2.4 in) |
| 2024 | 59.2 mm (2.3 in) |
| 2025 | 42.5 mm (1.7 in) |
| 2026 | 54.6 mm (2.1 in) |
Longest dry spell (CDD)
| Year | Longest dry spell (CDD) |
|---|---|
| 1940 | 41 days |
| 1941 | 28 days |
| 1942 | 107 days |
| 1943 | 98 days |
| 1944 | 57 days |
| 1945 | 45 days |
| 1946 | 60 days |
| 1947 | 74 days |
| 1948 | 52 days |
| 1949 | 51 days |
| 1950 | 40 days |
| 1951 | 48 days |
| 1952 | 66 days |
| 1953 | 59 days |
| 1954 | 34 days |
| 1955 | 53 days |
| 1956 | 44 days |
| 1957 | 94 days |
| 1958 | 31 days |
| 1959 | 54 days |
| 1960 | 66 days |
| 1961 | 50 days |
| 1962 | 68 days |
| 1963 | 41 days |
| 1964 | 32 days |
| 1965 | 28 days |
| 1966 | 65 days |
| 1967 | 65 days |
| 1968 | 50 days |
| 1969 | 74 days |
| 1970 | 50 days |
| 1971 | 40 days |
| 1972 | 41 days |
| 1973 | 55 days |
| 1974 | 49 days |
| 1975 | 43 days |
| 1976 | 38 days |
| 1977 | 48 days |
| 1978 | 50 days |
| 1979 | 52 days |
| 1980 | 89 days |
| 1981 | 43 days |
| 1982 | 37 days |
| 1983 | 30 days |
| 1984 | 24 days |
| 1985 | 37 days |
| 1986 | 49 days |
| 1987 | 80 days |
| 1988 | 43 days |
| 1989 | 69 days |
| 1990 | 32 days |
| 1991 | 46 days |
| 1992 | 85 days |
| 1993 | 53 days |
| 1994 | 68 days |
| 1995 | 25 days |
| 1996 | 37 days |
| 1997 | 28 days |
| 1998 | 36 days |
| 1999 | 77 days |
| 2000 | 79 days |
| 2001 | 52 days |
| 2002 | 61 days |
| 2003 | 72 days |
| 2004 | 34 days |
| 2005 | 73 days |
| 2006 | 78 days |
| 2007 | 81 days |
| 2008 | 59 days |
| 2009 | 34 days |
| 2010 | 36 days |
| 2011 | 88 days |
| 2012 | 105 days |
| 2013 | 36 days |
| 2014 | 33 days |
| 2015 | 35 days |
| 2016 | 72 days |
| 2017 | 47 days |
| 2018 | 79 days |
| 2019 | 70 days |
| 2020 | 45 days |
| 2021 | 39 days |
| 2022 | 67 days |
| 2023 | 63 days |
| 2024 | 48 days |
| 2025 | 53 days |
| 2026 | 47 days |
Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.
Frost Dates and Growing Season
86 years with a frostAcross 86 years with a frost, the median last spring frost at Boise Air Terminal falls on 4 May and the median first autumn frost on 13 October, which leaves a median of 160 days between them.
In 1996 to 2025 the median growing season was 178 days. That is 21 days more than in 1940 to 1969.
Fitted over all years, the growing season changes by +3.0 days per decade at this station.
| Measure | Median, all years | Earliest period (1940 to 1969) | Recent period (1996 to 2025) | Recent against earliest | Fitted trend |
|---|---|---|---|---|---|
| Last spring frost | 4 May | 5 May | 1 May | 4 days earlier | -1.6 days per decade |
| First autumn frost | 13 October | 13 October | 22 October | 9 days later | +1.4 days per decade |
| Growing days | 160 days | 157 days | 178 days | 21 days more | +3.0 days per decade |
A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.
Rainfall Return Levels
86 years, 1940 to 2025A day with at least 20.6 mm (0.8 in) of rain is expected about once in 2 years. A day with at least 50.3 mm (2.0 in) of rain is expected about once in 100 years.
| Expected about once in | A day with at least | Note |
|---|---|---|
| 2 years | 20.6 mm (0.8 in) | |
| 5 years | 27.3 mm (1.1 in) | |
| 10 years | 32.1 mm (1.3 in) | |
| 25 years | 38.9 mm (1.5 in) | |
| 50 years | 44.4 mm (1.7 in) | |
| 100 years | 50.3 mm (2.0 in) | Longer than the 86 years of record |
The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 86 years of values from 1940 to 2025.
A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.
The largest wettest-day totals in the fit: 48.5 mm (1.9 in) in 1958; 45.0 mm (1.8 in) in 1990; 43.9 mm (1.7 in) in 1976.
Station Changes
3 suspected3 changes were suspected in the annual mean temperature of Boise Air Terminal, at 1968, 1976 and 1997. Each is measured against neighbouring stations.
- Relative to 5 neighbouring stations, the station's annual mean temperature from 1968 ran 0.4 C (0.7 F) higher than in the years before (likely change).
- Relative to 5 neighbouring stations, the station's annual mean temperature from 1976 ran 0.6 C (1.0 F) lower than in the years before (likely change).
- Relative to 5 neighbouring stations, the station's annual mean temperature from 1997 ran 0.7 C (1.3 F) higher than in the years before (likely change).
| Year | Shift (C) | Shift (F) | Strength | Neighbours |
|---|---|---|---|---|
| 1968 | +0.4 | +0.7 | likely | 5 |
| 1976 | -0.6 | -1.0 | likely | 5 |
| 1997 | +0.7 | +1.3 | likely | 5 |
Possible change at the station (a move, a new instrument or a new site); the record is kept as measured. A "likely" change has a larger test statistic than a "possible" one. Neither says why the station differs from its neighbours. How changes are found, and the largest ones.
Climate Twins
2011 to 2025 against 1961 to 1990Over 2011 to 2025, Boise Air Terminal had a mean temperature of 12.2 C (54.0 F) and 318.3 mm (12.5 in) of rain a year. The 3 stations whose 1961 to 1990 climate was closest to that are Brownlee Dam (United States, 151 km away), Holbrook (United States, 1,095 km away) and Gateway 1ENE (United States, 816 km away).
| Twin station | Country | Distance away | Mean temperature, 1961-1990 | Rain a year, 1961-1990 | Climate difference |
|---|---|---|---|---|---|
| Brownlee Dam | United States | 151 km (94 mi) | 12.0 C (53.7 F) | 435.9 mm (17.2 in) | 0.73 |
| Holbrook | United States | 1,095 km (680 mi) | 11.9 C (53.5 F) | 238.5 mm (9.4 in) | 0.96 |
| Gateway 1ENE | United States | 816 km (507 mi) | 11.8 C (53.2 F) | 299.4 mm (11.8 in) | 0.97 |
Twins are stations, not cities. A twin is one of the three stations at least 100 km away whose earlier climate is closest to this station's recent one, so a close match does not mean the two places look alike in other ways. A station move or a gap in a record can change that station's averages. The list describes past climate; it is not a forecast and does not say what caused any change. How twins are found, and a search for any station.
Download the Data
Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-16 (16 October 2026). Records are computed by this site and are not official.
Data as of . Last revised (2026-10-16).